Self-locking bone screw for attaching an implant

摘要

A fixation plate system includes a plate with elongated slots, and first and second anchors for attaching the plate to vertebrae. The first and second anchors have different head configurations that are selected by the surgeon to control how settlement occurs at each fused segment. The head of the first fastener is insertable in any of the slots and resists translation. The head of the second fastener is insertable in any of the slots in free sliding engagement to allow translation of the head in that slot. In one method of use, the surgeon selects a segment where settling needs to be limited, and uses the first fastener to fix the plate near the segment and limit settling at that segment. The first and second fasteners have a built-in spring that assists in securing the fasteners in the plate.